Hypoglycemic mechanisms of Polygonatum sibiricum polysaccharide in db/db mice via regulation of glycolysis/gluconeogenesis pathway and alteration of gut microbiota

Polygonati Rhizoma polysaccharide suppresses microglial activation and promotes functional recovery of spinal cord via improving intestinal microbiota

Spinal cord injury (SCI) can disrupt the gut microbiome and metabolites, impacting prognosis, substantially impairing quality of life, and leading to high socioeconomic costs (Jing et al., 2021). Recent studies indicate that plant polysaccharides exhibit antimicrobial, anti-inflammatory, and immune-enhancing properties, contributing positively to various neurological disorders; however, their role in SCI remains uncertain (Hou et al., 2020 [2]; Aswini et al., 2021 [3]; Dou et al., 2019 [4]). Polygonati Rhizoma polysaccharide (PRP) has shown anti-inflammatory and immunoregulatory effects, but its role in SCI remains unexplored. This study investigated whether PRP facilitates functional recovery after SCI by modulating the gut microbiota and SCFA levels. PRP was administered to SCI mice, and motor function was assessed using DeepLabCut-based behavioral analysis. Histological evaluations were performed with H&E, Nissl, and immunofluorescence staining. Microglial activation and inflammation were analyzed by Western blot and immunofluorescence. Gut microbiota composition and SCFAs were examined through 16S rRNA sequencing and targeted metabolite profiling. PRP treatment significantly improved motor function, reduced microglial activation, and attenuated neuroinflammation. These effects were associated with restoration of microbial diversity and elevated butyrate levels. This study highlights the role of the gut-brain axis in neural regeneration and suggests PRP as a promising therapeutic candidate for SCI.

Medicinal and edible homologous poly/oligo-saccharides: Structural features, effect on intestinal flora and preventing and treating type 2 diabetes, and their applications: A review

Type 2 diabetes mellitus (T2DM) is the third most common chronic metabolic disorder worldwide and seriously dangerous. Novel therapeutics are sought due to the paucity of safe and effective metabolic disorder-related diabetes medicines. Intestinal flora impacts glucose and lipid balance, making it a unique T2DM therapeutic target. Due to gut fermentation, poly/oligo-saccharides are highly beneficial prebiotic carbohydrates for intestinal health. Moreover, supplementation with naturally occurring medicinal and edible homologous traditional Chinese medicines (MEHTCM) poly/oligo-saccharides has significant antidiabetic effects with few side effects. Now, a comprehensive review of research developments of MEHTCM poly/oligo-saccharides was presented to explore their prospects. We outlined the structural characteristics, structure classification, and structure-activity relationships. Notably, structure-activity relationships illustrated that molecular weight, monosaccharide composition, and glycosidic bond type could influence the hypoglycemic activity and prebiotic effect of MEHTCM poly/oligo-saccharides. Additionally, the review systematically summarized the effect and potential mechanism of MEHTCM poly/oligo-saccharide on T2DM, focusing on gut microbiota. The potential applications in formulations for special medical purposes, common food, health care product, agriculture and other fields have also been summarized. This review emphasizes MEHTCM poly/oligo-saccharides' potential as prebiotics for T2DM treatment. This information provides new insights and a theoretical foundation for MEHTCM poly/oligo-saccharide nutritional and medicinal research.

Traditional Chinese medicine in the prevention of diabetes mellitus and cardiovascular complications: mechanisms and therapeutic approaches

Diabetes mellitus (DM) is a chronic endocrine and metabolic disorder characterized by persistent hyperglycemia that poses serious threats to human health and quality of life. The morbidity, disability, and mortality rates of cardiovascular complications stemming from chronic hyperglycemia are primary factors affecting the lifespan of patients with diabetes. Currently, there is no cure for DM. Standard biomedical treatments mostly control the symptoms using insulin injections or oral hypoglycemic drugs. Although the effect of standard biomedical therapy is remarkable, its long-term use is prone to toxic side effects. Numerous studies have recently found that Traditional Chinese Medicine (TCM) has strong advantages in the prevention and treatment of DM and cardiovascular complications (DACC). The collection, processing, preparation and clinical use of TCM are guided by the theory of TCM and follow the "holistic concept." Multiple components, pathways, and targets form the basis for the use of TCM in treating multiple parts and organs of the body simultaneously. TCM is mainly derived from natural medicines and their processed products and has fewer side effects. TCM is clinically used as compound prescriptions, botanical drugs, and monomers. TCM, either independently or in combination with standard biomedical treatments, has shown unique therapeutic advantages. This review aimed to explore the recently reported mechanisms of action of TCM in the prevention and treatment of DACC. These findings will aid the optimization of the current therapy or formation of a therapeutic schedule for integrated TCM and standard biomedical treatments.

Pumpkin Soluble Dietary Fiber instead of Insoluble One Ameliorates Hyperglycemia via the Gut Microbiota-Gut-Liver Axis in db/db Mice

Pumpkin extract has been shown to alleviate hyperglycemic symptoms by improving glucose metabolism disorders. However, the specific active components responsible for its hypoglycemic effects and the underlying molecular mechanisms remain unclear. In this study, db/db mice underwent a 4-week dietary intervention with two pumpkin flours (PF1 and PF2), total dietary fiber (TDF), soluble dietary fiber (SDF), and insoluble dietary fiber (IDF), with acarbose serving as a positive control. Our results revealed that pumpkin components significantly altered the gut microbiota, characterized by a reduction in diabetes-related bacteria and an increase in short-chain fatty acid (SCFA)-producing bacteria, including Bacteroides, Akkermansia, and Lachnospiraceae_NK4A136 group. Additionally, pumpkin components significantly increased fecal SCFA levels and upregulated the expression of SCFA receptor GPR43, potentially promoting GLP-1 secretion. Notably, pumpkin components significantly reduced fasting blood glucose and serum insulin levels and inhibited gluconeogenesis. This effect may be ascribed to the inhibition of the cAMP/PKA/CREB signaling pathway coupled with the activation of the PI3K/AKT signaling pathway. Our research indicated that pumpkin flour and dietary fiber alleviated hyperglycemia through the gut-liver axis, with SDF contributing the most to the hypoglycemic effect. These findings suggest that pumpkin components may serve as an adjunct nutritional intervention to ameliorate hyperglycemia.

Evidence of traditional Chinese medicine for treating type 2 diabetes mellitus: from molecular mechanisms to clinical efficacy

CONTEXT

The global prevalence of type 2 diabetes mellitus (T2DM) has increased significantly in recent decades. Despite numerous studies and systematic reviews, there is a gap in comprehensive and up-to-date evaluations in this rapidly evolving field.

OBJECTIVE

This review provides a comprehensive and current overview of the efficacy of Traditional Chinese Medicine (TCM) in treating T2DM.

METHODS

A systematic review was conducted using PubMed, Web of Science, Wanfang Data, CNKI, and Medline databases, with a search timeframe extending up to November 2023. The search strategy involved a combination of subject terms and free words in English, including 'Diabetes,' 'Traditional Chinese Medicine,' 'TCM,' 'Hypoglycemic Effect,' 'Clinical Trial,' and 'Randomized Controlled Trial.' The studies were rigorously screened by two investigators, with a third investigator reviewing and approving the final selection based on inclusion and exclusion criteria.

RESULTS

A total of 108 relevant papers were systematically reviewed. The findings suggest that TCMs not only demonstrate clinical efficacy comparable to existing Western medications in managing hypoglycemia but also offer fewer adverse effects and a multitarget therapeutic approach. Five main biological mechanisms through which TCM treats diabetes were identified: improving glucose transport and utilization, improving glycogen metabolism, promoting GLP-1 release, protecting pancreatic islets from damage, and improving intestinal flora.

CONCLUSIONS

TCM has demonstrated significant protective effects against diabetes and presents a viable option for the prevention and treatment of T2DM. These findings support the further exploration and integration of TCM into broader diabetes management strategies.

Polysaccharides in Medicinal and Food Homologous Plants regulate intestinal flora to improve type 2 diabetes: Systematic review

BACKGROUND

Medicinal and food homologous plants (MFHPs) which can improve Type 2 Diabetes Mellitus (T2DM) draw significant attention among the public due to their low toxicity and more safety. Polysaccharides, one of the various active components of MFHPs, are recognized as effective modulators of the intestinal flora. By altering the composition of intestinal flora and affecting their metabolic products, polysaccharides can improve T2DM, making them a central focus of anti-diabetic research.

PURPOSE

The purpose of this study is to systematically review the mechanism by which polysaccharides from MFHPs (MFHPPs) regulate the composition of intestinal flora and its metabolic products to improve T2DM.

METHODS

This study follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and conducts a comprehensive search on the PubMed, Web of Science and Embase databases. All experimental articles published up to March 4, 2024, are included in the search.

RESULTS

Among the 5733 articles reviewed, 29 were selected, covering 22 different MFHPs. MFHPPs can improve T2DM, particularly in lowering blood glucose levels, with consistent results. MFHPPs can regulate the diversity of intestinal flora in T2DM animal models, primarily affecting four phyla: decreasing Firmicutes and Proteobacteria while increasing Bacteroidetes and Actinobacteriota. At the genus level, the improvement of T2DM by MFHPPs is associated with the modulation of 12 key genera: Allobaculum, Akkermansia, Bifidobacterium, Lactobacillus, Helicobacter, Halomonas, Olsenella, Oscillospira, Shigella, Escherichia-Shigella, Romboutsia and Bacteroides. At the molecular level, MFHPPs primarily act by modulating the intestinal flora to increase short-chain fatty acid levels, promote the secretion of glucagon-like peptide-1, influence the IGF1/PI3K/AKT signaling pathway, or the PI3K/AKT/GSK-3β pathway, to lower blood glucose levels. They may also improve T2DM by working in glucose metabolism through the "microbiota-gut-organ" axis. MFHPPs can also alleviate T2DM by mitigating inflammation and oxidative stress: MFHPPs regulate intestinal flora to reduce lipopolysaccharide "leakage" and enhance intestinal mucosal permeability to tackle the inflammation associated with T2DM; MFHPPs enhance the expression of oxidative stress-related enzymes to alleviate oxidative stress and improve T2DM. Lastly, from a metabolic pathway perspective, MFHPPs are primarily involved in the metabolism of amino acids and their derivatives, carbohydrate metabolism and glutathione metabolism.

CONCLUSION

MFHPPs can improve T2DM by enhancing the composition of intestinal flora, regulating its metabolic products to promote insulin secretion, inhibiting glucagon-like peptide secretion, facilitating glycogen synthesis, reducing inflammation levels and alleviating oxidative stress. Furthermore, MFHPPs demonstrate potential protective effects on critical organs such as the pancreas, liver, kidneys and heart. Therefore, MFHPPs demonstrate significant clinical potential. However, most studies can only indicate the potential of MFHPPs intervention in improving T2DM through the intestinal flora. The causality between MFHPPs regulating the intestinal flora and T2DM requires further investigation.

Research progress on medicinal components and pharmacological activities of polygonatum sibiricum

ETHNOPHARMACOLOGICAL RELEVANCE

Polygonatum sibiricum, commonly known as Siberian Solomon's seal, is a traditional herb widely used in various traditional medical systems, especially in East Asia. In ancient China, the use of polygonatum sibiricum in medicine and food was mentioned in Li Shizhen's Bencao Gangmu of traditional Chinese medicine (TCM). It was also used in history of India in Vedic medicine. The plant is rich in bioactive substances such as polysaccharides, saponins, flavonoid and alkaloids.

AIM OF THE REVIEW

The aim of this review is to understand the pharmacological and pharmacokinetics research progress of the major components of polygonatum sibiricum, and to prospect its potential application and development in the treatment of various diseases.

MATERIALS AND METHODS

We conducted a systematic literature search against major online databases on the Web, including PubMed, ancient books, patents, PubMed, Wiley, Google Scholar, Web of Science, and others. We select the pharmacological process and mechanism of the main components of polygonatum sibiricum in a variety of diseases, and make a strict but careful supplement and in-depth elaboration to this review.

RESULTS

Several studies have demonstrated the strong antioxidant properties of polygonatum extract, which can be attributed to the presence of flavonoids and other polyphenol compounds; for diabetes and other metabolic-related diseases, polygonatum saponins have particular advantages in regulating intestinal flora and lipoprotein concentration in organisms. In addition, the polysaccharides extracted from this plant have a strong anti-inflammatory effect, which is related to its ability to regulate proinflammatory cytokine and mediators. In the aspect of anti-tumor effect, polygonatum derivatives can induce cancer cell apoptosis mainly by adjusting the cell membrane potential and cell cycle. It is worth noting that the combined action of the main components of polygonatum also offers promising solutions for the treatment of the disease.

CONCLUSION

Polygonatum polysaccharide has therapeutic effects on many diseases by adjusting cell signal pathways, polygonatum sibiricum have significant advantages in regulating intestinal flora, inducing apoptosis of tumor cells, activating antioxidant processes, etc. Further research and basic exploration are needed to prove the function and mechanisms of the main components of polygonatum sibiricum on related diseases. The study on the immunomodulatory properties of polygonatum revealed its potentiality of enhancing immune function, which made it an interesting subject for further exploration in the field of immunotherapy.

Gut Microbiota Targeted Approach by Natural Products in Diabetes Management: An Overview

PURPOSE OF REVIEW

This review delves into the complex interplay between obesity-induced gut microbiota dysbiosis and the progression of type 2 diabetes mellitus (T2DM), highlighting the potential of natural products in mitigating these effects. By integrating recent epidemiological data, we aim to provide a nuanced understanding of how obesity exacerbates T2DM through gut flora alterations.

RECENT FINDINGS

Advances in research have underscored the significance of bioactive ingredients in natural foods, capable of restoring gut microbiota balance, thus offering a promising approach to manage diabetes in the context of obesity. These findings build upon the traditional use of medicinal plants in diabetes treatment, suggesting a deeper exploration of their mechanisms of action. This comprehensive manuscript underscores the critical role of targeting gut microbiota dysbiosis in obesity-related T2DM management and by bridging traditional knowledge with current scientific evidence; we highlighted the need for continued research into natural products as a complementary strategy for comprehensive diabetes care.

The Supplementation of Berberine in High-Carbohydrate Diets Improves Glucose Metabolism of Tilapia (Oreochromis niloticus) via Transcriptome, Bile Acid Synthesis Gene Expression and Intestinal Flora

Berberine is an alkaloid used to treat diabetes. This experiment aimed to investigate the effects of berberine supplementation in high-carbohydrate diets on the growth performance, glucose metabolism, bile acid synthesis, liver transcriptome, and intestinal flora of Nile tilapia. The six dietary groups were the C group with 29% carbohydrate, the H group with 44% carbohydrate, and the HB1-HB4 groups supplemented with 25, 50, 75, and 100 mg/kg of berberine in group H. The results of the 8-week trial showed that compared to group C, the abundance of Bacteroidetes was increased in group HB2 (p < 0.05). The cholesterol-7α-hydroxylase (CYP7A1) and sterol-27-hydroxylase (CYP27A1) activities were decreased and the expression of FXR was increased in group HB4 (p < 0.05). The pyruvate carboxylase (PC) and phosphoenolpyruvate carboxykinase (PEPCK) activities was decreased in group HB4 (p < 0.05). The liver transcriptome suggests that berberine affects carbohydrate metabolic pathways and primary bile acid synthesis pathways. In summary, berberine affects the glucose metabolism in tilapia by altering the intestinal flora structure, enriching differentially expressed genes (DEGs) in the bile acid pathway to stimulate bile acid production so that it promotes glycolysis and inhibits gluconeogenesis. Therefore, 100 mg/kg of berberine supplementation in high-carbohydrate diets is beneficial to tilapia.

Coreopsis tinctoria improves energy metabolism in obese hyperglycemic mice

Coreopsis tinctoria (CT) improves energy metabolism. However, the role of CT in alleviating obesity-induced hyperglycemia by targeting the liver remains unknown. Therefore, this article aims to explore the mechanism by which CT improves energy metabolism and resists hyperglycemia. The water and ethanol extracts of CT were administered to high-fat diet-induced (HFD) obese C57BL/6J mice at a dose of 4 g/kg.bw (low-dose water extract, WL; low-dose ethanol extract, EL) or 10 g/kg.bw (high-dose water extract, WH; high-dose ethanol extract, EH). Mice that consumed a maintenance diet (LFD) were included as blank controls. Network pharmacology, liquid chromatography-mass spectrometry (LC-MS), L02 cell cultivation, and liver transcriptomics were used to examine the mechanism and functional components of CT against obesity-induced hyperglycemia. The results indicated that WL significantly (p < 0.05) alleviated glucose intolerance and insulin resistance in obesity-induced hyperglycemia. Kaempferol is the main active compound of CT, which demonstrated significant (p < 0.05) anti-hyperglycemic effects in obese mice and L02 cells. Finally, kaempferol significantly (p < 0.05; fold change >1.2) shifted the genes involved in carbon metabolism, glycolysis/gluconeogenesis, and the mitogen-activated protein kinase (MAPK) pathways toward the trend of LFD, indicating that it exerts an anti-hyperglycemic effect through these molecular mechanisms. Overall, oral intake of CT lowers blood glucose and improves insulin sensitivity in mice with obesity-induced hyperglycemia. Kaempferol is the primary functional component of CT.

Review of studies on polysaccharides, lignins and small molecular compounds from three Polygonatum Mill. (Asparagaceae) spp. in crude and processed states

Since ancient times, Polygonatum Mill. (Asparagaceae) has been utilized as a medicinal and culinary resource in China. Its efficacy in treating various illnesses has been well documented. Traditional processing involves the Nine-Steam-Nine-Bask method, which results in a reduction of toxicity and enhanced effectiveness of Polygonatum. Many substances, such as polysaccharides, lignins, saponins, homoisoflavones, alkaloids, and others, have been successfully isolated from Polygonatum. This review presents the research progress on the chemical composition of three crude and processed Polygonatum, including Polygonatum sibiricum Redouté (P. sibiricum), Polygonatum kingianum Collett & Hemsl (P. kingianum), and Polygonatum cyrtonema Hua (P. cyrtonema). The review also includes the pharmacology of Polygonatum, specifically on the pharmacology of polysaccharides both before and after processing. Its objective is to provide a foundation for uncovering the significance of the processing procedure, and to facilitate the development and utilization of Polygonatum in clinical practice.